Cement-based dry or ready-to-use compositions, for mortars or plasters, are generally in the form of powdered products and are known to have a high dust emission rate, for example during production, packaging or use thereof.
This dust emission presents health problems for workers and their working conditions.
In addition, the dust soils the local environment in which the materials are stored or handled (factory or construction site).
Moreover, the finest particles that escape more easily can be adjuvants or additives in small amounts. However, these constituents are costly and play an important role in the composition or in the properties of the end material. The loss of these constituents may modify the constitution of the composition and result in a loss in performance of the end material.
Furthermore, the fine particles of the compositions can be hygroscopic and/or electrostatic and can cause additional problems of implementation or use of the dry compositions, for example problems of fluidity, binding and risk of dust explosions.
To reduce dust emissions, “anti-dust” additives have been used in the formulation of compositions.
For example, reference can be made to U.S. Pat. No. 6,464,776, which describes the use of polytetrafluoroethylene for limiting the dust emission of cement or mortar compositions. However, these constituents promote the penetration of air in the composition, which alters the physicochemical properties of the material, resulting in the need to add additional defoaming additives.
International Publication No. WO 2006/084588 describes the use of hydrocarbon compounds such as additives for reducing the dust produced by dry compositions for construction. However, among the known additives, some are ineffective and large amounts of these additives are needed to obtain an “anti-dust” effect.
In addition, some additives are costly or need to be prepared by processes that are restrictive or difficult to implement.
Moreover, some additives can impair the properties and performances of mortars or concretes, and, for example, the workability, resistance, adhesion properties, waterproofing and durability properties.
Furthermore, the addition of “anti-dust” additives can impair the fire behavior of the materials (for example, mortars, concretes, plasters). The presence of “anti-dust” additives can impair the fire resistance of the composition.
Therefore, it would be beneficial to mitigate these defects and disadvantages of the related art. For example, it would be beneficial to provide dry compositions for cement-based materials making it possible to effectively limit dust emissions and loss during production, transport or handling, while also enabling the materials obtained to preserve good fire resistance properties. For example, it would be beneficial to provide inexpensive, practical and easy-to-use compositions with, for example, good properties of stability, fluidity, etc. In addition, it would be beneficial to provide dry compositions enabling end materials to be obtained having good physicochemical properties, for example, workability, durability, compression strength, fire resistance, and so on.